【摘要】 本文针对分汊河口一侧河道整治工程对工程汊及非工程汊水动力的影响问题,采用数学模型试验方法,建立了潮汐分汊河口概化数学模型,计算了整治工程(双导堤与丁坝)前后水动力变化,分析了主要分潮M2、M4的潮位、流速沿程变化规律以及工程后丁坝局部流速流向特征,讨论了潮波的变形及不对称性。结果显示,整治工程导致工程汊分流比减小,工程区域内流速增加,工程区外流速减小,非工程汊整体流速增加。工程汊的潮流变形及不对称性均较工程前有所增强,导致外海泥沙盐水通过航槽向上游上溯的距离更长,坝田区内流速明显小于航槽流速,并呈明显的旋转流态势,导致坝田淤积。更多还原

【Abstract】 A schematized numerical model of a bifurcated estuary is established to study the hydrodynamic impact of the river regulation project. The hydrodynamics variations before and after the project are calculated. The variation of the water level and current velocity amplitude of the main tidal component M2 and M4 tide along the branch are analyzed. At the same time,the characteristics of local current velocity and direction in the spur dike area after the project are analyzed. In addition,the tidal distortion and asymmetry before and after the project are discussed. The results show that,the regulation project leads to a decrease in the flow portion of the project branch,the flow rate in the project area increases while outside the project area decreases. The overall flow rate of the non-engineering branch increases. The tidal deformation and asymmetry of the engineering branch are enhanced compared with that before the project,which causes the offshore sediment and saltwater to travel more upstream. The current velocity in the dam sheltering area is significantly smaller than that in the channel,and it shows a rotating flow,which may lead to sediment siltation in this area.更多还原